Rumen-stable pellets

Abstract

Pellets adapted to be orally administered to ruminants are disclosed. The pellets have a core comprising a nutrient and/or medicament, of which the pH is raised to a predetermined level by the addition of a basic substance. A coating which protects the core in the environment of the rumen is also provided to allow utilization of the core in the abomasum and/or intestine. The coating comprises a polymeric matrix which is resistant to the mildly acidic environment of the rumen and may include a hydrophobic substance dispersed throughout the continuous matrix. The continuity of the polymerix matrix is destroyed in the more acidic environment of the abomasum.

We claim: 
     
       1. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) mixing with said core material a physiologically acceptable basic substance in sufficient quantity to raise the pH of the mixture above about 5.68,   (b) forming the mixture into self-supporting pellets, and   (c) coating said mixture with a composition comprising a film-forming polymeric material containing at least one basic amino grouping, the nitrogen content of which is from about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.   
     
     
       2. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) forming the core material into self-supporting pellets,   (b) applying a first coating on said core material with a basic substance in an amount of from about 1 to about 20% of the weight of the core, and   (c) applying a second coating over said first coating, said second coating being a composition comprising a film-forming polymeric material containing at least one basic amino grouping, the nitrogen content of which is from about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said second coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.   
     
     
       3. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) mixing with said core material a basic substance selected from the group consisting of magnesium oxide, magnesium hydroxide, magnesium carbonate, calcium oxide, calcium hydroxide, calcium carbonate, aluminum hydroxide and basic aluminum acetate in sufficient quantity to raise the pH of the mixture above about 5.75,   (b) forming the mixture into self-supporting pellets, and   (c) coating said mixture with a composition comprising a film-forming polymeric material containing at least one basic amino grouping, the nitrogen content of which is from about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.   
     
     
       4. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) forming the core material into self-supporting pellets,   (b) applying a first coating on said core material with a basic substance selected from the group consisting of magnesium oxide, magnesium hydroxide, magnesium carbonate, calcium oxide, calcium hydroxide, calcium carbonate, aluminum hydroxide and basic aluminum acetate, and   (c) applying a second coating over said first coating, said second coating comprising a film-forming polymeric material containing at least one basic amino grouping, the nitrogen content of which is about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.   
     
     
       5. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) mixing with said core material a basic substance selected from the group consisting of magnesium oxide, magnesium hydroxide, magnesium carbonate, calcium oxide, calcium hydroxide, calcium carbonate, aluminum hydroxide and basic aluminum acetate in sufficient quantity to raise the pH of the mixture above about 5.75,   (b) forming the mixture into self-supporting pellets, and   (c) coating said mixture with a composition comprising an aliphatic or aromatic basic amino-containing film-forming polymeric material, the nitrogen content of the basic amino grouping of said polymeric material being from about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material selected from the group consisting of fatty acids having from 10 to 32 carbon atoms, aluminum salts of fatty acids having from 10 to 32 carbon atoms, dimer acids, trimer acids, waxes, resins, polymers containing hydrophobic chemical groups and polycarboxylic acids having a ratio of from 10 to 22 carbon atoms per carboxyl group and a molecular weight of from 400 to 1000, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.   
     
     
       6. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) forming the core material into self-supporting pellets,   (b) applying a first coating on said core material with a basic substance selected from the group consisting of magnesium oxide, magnesium hydroxide, magnesium carbonate, calcium oxide, calcium hydroxide, calcium carbonate, aluminum hydroxide and basic aluminum acetate, and   (c) applying a second coating over said first coating, said second coating comprising an aliphatic or aromatic basic amino-containing film-forming polymeric material, the nitrogen content of the basic amino grouping of said polymeric material being from about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material selected from the group consisting of fatty acids having from 10 to 32 carbon atoms, aluminum salts of fatty acids having from 10 to 32 carbon atoms, dimer acids, trimer acids, waxes, resins, polymers containing hydrophobic chemical groups and polycarboxylic acids having a ratio of from 10 to 22 carbon atoms per carboxyl group and a molecular weight of from 400 to 1000, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.   
     
     
       7. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) mixing with said core material a basic substance selected from the group consisting of magnesium oxide, magnesium hydroxide, magnesium carbonate, calcium oxide, calcium hydroxide, calcium carbonate, aluminum hydroxide and basic aluminum acetate in sufficient quantity to raise the pH of the mixture above about 5.75,   (b) forming the mixture into self-supporting pellets, and   (c) coating said mixture with a film-forming polymer comprising cellulose propionate morpholinobutyrate, polyvinyl pyridine and derivatives of polyvinyl pyridine, the nitrogen content of the basic amino grouping of said polymeric material being from about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material selected from the group consisting of fatty acids having from 12 to 32 carbon atoms, aluminum salts of fatty acids having from 12 to 32 carbon atoms, dimer acids, trimer acids, waxes, resins, polymers containing hydrophobic chemical groups and polycarboxylic acids having a ratio of from 10 to 22 carbon atoms per carboxyl group and a molecular weight of from 400 to 1000, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.   
     
     
       8. A method of preparing pellets having a core material and coating adapted for oral administration to ruminants wherein said core material is beneficial to the ruminant postruminally, said coating protecting the core material in the rumen and releasing it in the abomasum, said method comprising (a) forming the core material into self-supporting pellets,   (b) applying a first coating on said core material with a basic substance selected from the group consisting of magnesium oxide, magnesium hydroxide, magnesium carbonate, calcium oxide, calcium hydroxide, calcium carbonate, aluminum hydroxide and basic aluminum acetate,   (c) applying a second coating over said first coating, said second coating comprising a film-forming polymeric material containing at least one basic amino grouping and comprising at least one polymer, copolymer or blend of polymers having at least as a component part cellulose propionate morpholinobutyrate, polyvinyl pyridine and derivatives of polyvinyl pyridine, the nitrogen content of the basic amino grouping of said polymeric material being from about 2 to 14% by weight of the total molecular weight of said polymeric material, and a hydrophobic substance dispersed in said polymeric material selected from the group consisting of fatty acids having from 10 to 32 carbon atoms, aluminum salts of fatty acids having from 10 to 32 carbon atoms, dimer acids, trimer acids, waxes, resins, polymer containing hydrophobic chemical groups and polycarboxylic acids having a ratio of from 10 to 22 carbon atoms per carboxyl group and a molecular weight of from 400 to 1000, said hydrophobic substance being present in an amount between about 1 and 50% of the weight of the polymeric material, said coating making up about 5 to about 50% of the weight of said pellet and having a sticking temperature of greater than about 50° C.